Halacha states that if a person eats a raw vegetable where it is not customarily eaten raw, one says "shehakol" rather than "ha'admah"? What criteria decide"custom"? Does this rule change? E.g. - a few decades ago, few ate raw string beans, broccoli and cauliflower. Now, these are common humus-dipping veggies in the U.S.
The rules of berachos are dependent on the time and place. For example, in earlier times the bracha on carrots was shehakol since they were not eaten raw, whereas today their bracha is ha'adamah since they are eaten raw. Poskim in each generation evaluate the prevalent eating habits in their locale and issue a ruling accordingly. (Mishne Berurah 208: 18 citing Chayei Adam)
Mishne Berurah (205:3) writes that if the majority of people eat an item raw, even if it better cooked, the bracha is shehakol.
A similar thing occurs regarding Bishul Akum which does not apply to foods that are edible raw. Here, too, the status of each item is determined by the time and place. (Yoreh Deah, 113:1 Chelkas Bnyamin end of 5 and Biurim s.v. ne'echal)
- Fruits and vegetables which are normally eaten cooked but not raw – would receive their ideal bracha (He’eitz or Ha’adoma) when cooked, and only shehakol when eaten raw.
Examples would be: quince, and peanuts. (almost all peanuts are roasted, either in or out of the shell, and therefore raw peanuts would be shehakol.)
- Fruits and vegetables which are normally eaten raw and not cooked – receive their ideal bracha in their raw state, and a shehakol when cooked.
An examples would be: watermelon.
- Fruits and vegetables which are normally eaten either raw or cooked, receive their ideal bracha both when raw or cooked.
Examples: carrots, and apples
When deciding the normal manner of eating a particular fruit or vegetable – it is not that raw VS cooked has to be 50-50. As long as it wouldn’t be considered strange in that particular location – then it would maintain the ideal bracha.
Location: Although people generally cook or steam string beans and zucchini, it is also acceptable to eat them raw in America. Therefore, raw string beans would be Ha’adoma in America. However, since almost no one does so in Israel, raw string beans would be shehakol.
An American visiting Israel would follow his America customs, but one would makes aliyah would need to adopt Israel’s custom, and would now have to make shehakol on raw string beans.